


A Degree of Compatibility

by astolat



Series: Transformers works [15]
Category: Transformers Animated (2007)
Genre: Arranged Marriage, Consent Issues, Light Masochism, M/M, Other, consort
Language: English
Status: Completed
Published: 2019-02-06
Updated: 2019-02-06
Packaged: 2019-10-23 14:32:52
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 8,500
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17685287
Author URL: https://archiveofourown.org/users/astolat/pseuds/astolat
Summary: “And what’s the price for a Decepticon leader’s help these days?" Optimus said. "Head of his captor on a pike?”The Councillors started falling over each other hurriedly protesting, no, no, of course not, how could Optimus think, never—and Megatron laughed over them all and said, “It’s not your head I want to mount. I have demanded you as my consort.”“Okay, well, that’s—unexpected,” Optimus said, blankly.





	A Degree of Compatibility

**Author's Note:**

  * Translation into 中文 available: [兼容度](https://archiveofourown.org/works/17896424) by [landyschen](https://archiveofourown.org/users/landyschen/pseuds/landyschen)



Optimus was really unclear on how anyone had even come up with the plan of recruiting Megatron out of prison to help defend the planet in the first place, much less how the entire Council became convinced it was a good idea. Optimus was at the front himself at the time, desperately fighting to keep one of their energon-mining outposts from falling to the Marenil fleet; the first he heard of it was when they called him back to Cybertron and he caught up on his month of unread briefings on the way. He came off the ship ready to explain in very small words why this was a completely insane idea, only to pull up short the second he blazed into the Council chamber and found Megatron _already there_ , very much out of both his prison cell and his stasis cuffs.

“Why did you even bother sending for me!” Optimus yelled at the Council. “If you’d just shipped him straight to the front, he could have blasted me in the back before I even knew about any of this. You could’ve spared me that much.”

Megatron said, smirking at him, “You see, Optimus Prime, I have a condition for my services.”

Optimus stared at him, and then looked around the room. Literally the entire Council looked awkward and shifty and wouldn’t meet his eyes, and a strange cold fury fell on him. “Do you,” he said flatly, looking straight at them. “And what’s the price for a Decepticon leader’s help these days? Head of his captor on a pike?”

But they all jumped in their seats and started falling over each other hurriedly protesting, no, no, of course not, how could Optimus think, never—and Megatron laughed over them all and said, “It’s not your _head_ I want to mount. I have demanded you as my consort.”

“Okay, well, that’s—unexpected,” Optimus said, blankly.

#

Optimus wasn’t going along with this insanity, obviously; he made that clear right away to anyone who tried to say a word to him, until Megatron—who was clearly one of the _many_ people involved to have suffered a major interrupt to rational brain function—took him by the arm and dragged him over to the battlefield overview table and showed him the devastating details of the current Marenil offensives. Optimus had felt like his own defensive position was being held together by paint, but there were three more attacks going at the same time on other mining outposts that _weren’t_ holding together at all, the planetary shields had already been shut down for lack of energon, and Ultra Magnus was losing ground badly at the last critical space bridge junction. It wasn’t going to be a long war. Unless, hypothetically speaking, the Decepticons came in on their side of it.

“Except you _won’t_ ,” Optimus said, through his teeth. “I’m supposed to believe you’ll actually honor any arrangement—”

“I am making allowances because you have been taken by surprise, but soon you will begin to disappoint me,” Megatron said, as if he was under the delusion that Optimus _cared_ about disappointing him. “Do you imagine that I want to see the Marenil occupy and pillage all Cybertron?”

“In that case, you have to help us anyway!” Optimus threw back.

Megatron shrugged. “I am being asked to take on significant risk for little prospect of reward. Most of my soldiers will have to operate on the front. Once we defeat the Marenil, it would be all too easy for your Council to put the defense shields back up, lock most of us out, and simply slaughter those Decepticons remaining on the planet. I require—a show of faith.”

“By which you mean _me?_ ” Optimus said. “Why me?”

Megatron actually did emit a faint sigh of disappointment, which amazingly wasn’t enough to change Optimus’s mind, and neither was the begging, haranguing, and demanding of every Council member.

Then two hours later, the loud ongoing debate—if you could call it a _debate_ when all it involved was the entire Council making up increasingly ludicrous reasons why Optimus should be grateful for the opportunity to pop his panel for _Megatron_ , and Optimus saying _not gonna_ —was interrupted by an emergency broadcast from the spacebridge junction, Ultra Magnus’s voice crackling over the line, audio only, desperate and hoarse, saying, “We’ve lost our exit route. Comms about to go. We’ll take as many of them with us as we—” before his voice cut out abruptly.

Megatron said, coolly, “I can be there with two Decepticon elite squadrons in fifteen minutes.”

“Not if you’re still insisting on _spiking me first_ ,” Optimus snarled, wheeling on him with fists clenched.

“Under the circumstances, I’ll accept your word of honor,” Megatron said. “The formalities can wait until after we’ve stabilized the situation.”  

Optimus stood trembling, staring at him—Megatron was lounging on a massive chair they’d brought in just for him, and he looked about as concerned for Ultra Magnus as he did about the weather. “Fine,” Optimus said, harshly. “Assuming you _do_ stabilize the situation.” With any luck, Megatron would get _himself_ killed instead of Ultra Magnus.

#

Optimus’s luck remained about as good as it had ever been: Megatron stabilized the situation in a grand total of forty-nine hours. By the time he was done, there wasn’t any more active fighting going on; the Marenil had been kicked back to the last round of systems they’d conquered, and the defenses were busily getting reinforced in preparation for a counteroffensive. Megatron sailed back into the Council chamber with no more than a couple of new scuff marks and said, “Tomorrow morning, then.”

Shortly before dawn, Ratchet, Bulkhead, and Bumblebee got Optimus completely smashed on high grade and then toted him to the pledging ceremony. That order of events had seemed like a much better plan to Optimus before he was getting pledged to three copies of Megatron that all kept teleporting to different locations. On the bright side, his main processor still had a very fuzzy grip on reality by the time it was over and the Megatron on the right picked him up and carried him away to a private room and spread him out on a large recharging platform, and Optimus lolled back and said resignedly, “Go ahead, get it over with,” and opened his access panel.

Megatron just snorted and gave him another drink. Optimus poured it straight down the hatch—why not, maybe it was poison, that would’ve been great—only to be jolted instantly sober. “Oh, you jerk,” he said, propping himself up on his elbows and glaring at Megatron. “Think you’re going to get me to beg and plead or something?”

“Mm, I have ambitions,” Megatron said.

“Not a chance,” Optimus said.

“Do you know why I demanded you?” Megatron said.

“Sadism,” Optimus said.

“You do suffer most alluringly,” Megatron said. “And a certain degree of compatibility is necessary, I think, for a satisfactory arrangement—”

“A degree of _what?_ ”

Megatron looked at him with a thin red gleam in his eyes and then very slowly put out his massive hand. Optimus tensed, but Megatron only rested his fingertips on Optimus’s chest first, then eased forward until his whole hand was resting over the breastplate, so big it nearly covered the whole thing. “Come now,” he said softly, sliding it very gently up Optimus’s chest. “The edge of pain burning across your every sensory circuit…the widening rush of power flooding into your combat systems, the tightening of your servos…” He was still moving too slow for it to feel like a threat, even as his fingers curled around Optimus’s throat, and then abruptly he shoved Optimus down to the platform with a jarringly fast move that clacked his jaws painfully and knocked the air out of his intakes. Optimus gasped as his whole body jumped seventeen alert levels, a rush of fear and excitement flooding his systems, and his valve contracted hard, lubricant flowing—

“Yes,” Megatron purred, leaning over him. “Just so. Did you think I didn’t notice how you enjoyed it?”

Optimus shoved down the mortified impulse to squirm violently. “Do you think I care what you noticed?” he said through his teeth. “Just because—it doesn’t mean anything!”

“No,” Megatron agreed. “Nor would a little easy pleasure satisfy me.” His fingers slid caressingly along the base of Optimus’s cranial unit, his thumb pressing his chin up just to the limit where discomfort turned into pain, another helpless twinging going straight through Optimus’s neural pathways; he had to fight not to squirm again. “I have lived a million years and never before bound myself to a consort; do you think I would do so now for any small or petty reason?”

Optimus stared up at him instantly alarmed on a whole new level. Megatron had some kind of plan, he thought he could _use_ Optimus to— “Whatever you’re planning, I won’t go along with it,” he said through his teeth, grabbing at Megatron’s massive wrist and shoving at it, futilely. “Not in a thousand years, not in a million—”

Megatron snorted as he stretched himself out on the platform next to Optimus without ever taking the hand off his neck. “And still you fail to understand me. I think I could gladly tear out all their throats just for that.”

“What? Who are you—whose throats?” Optimus said, with some wariness, given that the most obvious throat right now was _his_.

“Your Council,” Megatron said. “Your Magnus. All of them. Tell me, Optimus Prime, if you found the Allspark lying in a human junkyard, surrounded by the twisted, rusting hulks of their dead machines, half buried under the disgusting squelch of their organic refuse, its gleam so obscured and begrimed that you yourself almost failed to see it, while the caretakers of that place exclaimed with delight over this or that piece of shiny scrap, would you gladly leave it there, in their hands?”

“What?” Optimus said. “Are you—you’re talking about—so _I’m_ the Allspark in this metaphor, and what, the Council is treating me like garbage and you’re the only one who sees how amazing I am?” It came out in rising hilarity; it was the most ridiculous thing he’d ever—

“They _gave_ you to me,” Megatron said. “Your Councillors fought to thrust you into my hands.”

Optimus stopped laughing, his mouth open. He stared at Megatron. “You had us over a _barrel!_ ”

Megatron waved a hand in impatience. “You yourself saw otherwise. Your Councillors could have refused me a single concession beyond merely allowing me to fight, and still I would have had to intervene. As it is, they undoubtedly _are_ planning to stab me in the back as soon as the Marenil are defeated. They only agreed to hand you over because they thought it a _trivial request_. You and your sworn oath a mere nothing that they gladly tossed at me like a half-rusted scrap, congratulating themselves on having found so cheap a way to make me think I had secured some kind of assurance from them.” His voice was heavy with disgust. “And this after they wasted you on command of a tertiary battlefield, while leaving Ultra Magnus to nearly lose the critical spacebridge line. Which you _allowed_ them to do,” he added, in irritated tones. “Tell me, would you have been satisfied to see our homeworld invaded if you could comfort yourself that at least you’d followed the orders of a gaggle of fools?”

Optimus lay there completely blank. He had absolutely no idea what to say. It all seemed ludicrous except for how the more he thought about it, the more it also seemed to actually be true. He wanted to say _they couldn’t know that you’d have helped,_ except he _had_ known that himself. He wanted to say _they aren’t going to break their promise,_ except of course the Council _would_ put the planetary shields back up and keep Megatron out if they had the chance. He wanted to say _they wouldn’t just hand me over for nothing,_ except they—they _had_ ; they hadn’t even tried to argue with Megatron for a second, not a single one of them had batted an eye at handing Optimus over to be—to be—

“I’m not—I’m just a Prime,” he managed, trying for the one thing he could answer. “I’m barely a few hundred stellar cycles out of the Academy. It would be stupid of them to—to give me the command—”

“Now _you_ are being stupid,” Megatron said, with contempt. “Or indulging yourself in willful blindness. Cease at once. You, who stood against me with a handful of repair bots and organics, bleating this nonsense. What would you have done at the spacebridge, with no more resources than Ultra Magnus had?”

Optimus stared at the ceiling, feeling strange and off-kilter; the second Megatron asked the question, the plan of battle unfolded itself through his brain almost instantly. He hadn’t consciously thought about it, he hadn’t _let_ himself think about it. He’d only thought about his own assignment, because he’d known that anything he could think of, Ultra Magnus would come up with something better, except—Ultra Magnus hadn’t, actually; he’d left two separate holes that the Marenil forces had exploited, and he’d put too many people at the choke point. “But,” Optimus said, confusedly. “But—I’m just—I’m—”

“The greatest military leader your people have ever produced,” Megatron said. “And now,” he added, with immense smugness, “you’re _mine_.”

“I’m not going to _help_ you,” Optimus said half absently, too busy trying to reorient his thinking to get as annoyed as that deserved.

“As though simply denying your services to the Council in future wouldn’t be a strategic victory on the order of the Battle of Korvonis,” Megatron said. “But I suspect you are not going to stand by when the Council breaks our pact and the Decepticons stranded on Cybertron are murdered.”

Optimus glared up at Megatron for that. “Nobody’s going to _murder_ anyone!”

“Just so,” Megatron said.

Optimus stopped with his mouth open again, lost. “I—that’s not—you’re—you’re wrong!” he burst out.

“About what?”

“About—about—everything!” Optimus said. “About—I don’t know! You’re just _wrong!_ And I—I _hate_ you!” It came out in desperation, and sounded like a newspark’s whine even to him. He glared at Megatron, who was _laughing_ at him.

“As entertaining as this has been, we must leave for the front in five hours,” Megatron said, still smirking. “Here’s the plan of battle for the advance on Arcadia and the outer mining colonies. Look it over and give me your recommendations.”

“This is your idea of pillow talk?” Optimus said sarcastically, then paused, because Megatron actually _was_ sending him the plan of battle. The _full_ plan of battle, complete with exhaustive details on Decepticon armaments, individual soldiers’ capabilities, his own tactical analysis— “Wait,” he said, wary. “What happened to—” he gestured meaningfully.

Megatron raised his brow ridge. “Were all those protests for show?”

“No!” Optimus said. “Also, you didn’t _listen_ to them!”

Megatron snorted. “ _You_ could have refused as well.”

“Ultra Magnus was about to die!” Optimus said. “And fine, maybe you’d have come in on our side in time to save _Cybertron_ , but don’t tell me you’d have saved _him_.”

“Of course not,” Megatron said. “I’d gladly have let the Marenil kill him and demolish a significant portion of your army and outer defenses first—it would save me the trouble of having to do it myself after the Marenil were defeated. I preferred to have you. That was the bargain you made. It seems reasonably fair.”

“So then—”

Megatron frowned at him, as if he still didn’t get it, then brightened and said. “Ahh… do you want me to hold you down and take you while you cry out in protest and fight me?” in a—a _hopeful_ way, as if he thought Optimus might in fact actually _want_ —Megatron’s red eyes gleaming over him, his spike pushing in with brutal force while Optimus struggled violently and futilely against—

“No!” Optimus managed, shoving that deeply unwanted image out of his head.

Megatron glanced down his body and raised an eyebrow. “Are you certain?”

“Yes,” Optimus said through his clenched jaw, resolutely ignoring any internal system reports that might in any way have contradicted him.

“Ah, well,” Megatron said. “We’ll see how you feel after the campaign.”

“I’ve seen you fight before. _Plenty_ of times.”

“Not on your side you haven’t. I’m not entirely certain why it makes so great a difference in Autobot value assessments, but I’ve seen the effect in action often enough to rely upon it. Perhaps I’ll get injured in battle defending you,” Megatron added thoughtfully. “That seems especially potent.”

“You—you’re deliberately thinking about getting hurt just to _impress_ me?” Optimus said.

Megatron shrugged. “Deliberately, no, but an injury or two is hardly unlikely. Nor particularly alarming—and I am _very_ eager to claim you completely.” He stroked a fingertip along the edge of Optimus’s helm to his mouth and gently traced the line of his lower lip while Optimus stared up at him helplessly. It was—it was—like talking to someone whose reality matrix had fallen down sideways. Someone very big and scary who wanted to _claim him_ , presumably by holding him down with one hand just like this and prying open his interface panel and—

“I’m— _not_ going to change my mind,” Optimus said. “And—and if you actually care what I want, then stop that and let go of me!”

Megatron sighed faintly. “Ah well. I can be patient a little longer.” And then he—took his hand away completely, letting his finger trail gently off Optimus’s mouth.

Optimus lay staring up at the ceiling in outraged betrayal as his low-level sensory subsystem broadcast an intensely disappointed complaint straight to his motivator and managed to get it to significantly downrate the emotional value of having told Megatron to stop, just because _he had_. “I hate you so much,” Optimus said bitterly.

#

Optimus didn’t feel _any_ differently, at _all_ , after watching Megatron demolish an entire squadron of enemy troops, and he also didn’t feel any differently after watching him take a Marenil pulse-spear to the side, he _didn’t_ , and he didn’t even feel any differently after Megatron anyway still dived directly into an active swarm of viper ships converging on their infantry advance and saved Bulkhead and Bumblebee.

“Have your sentiments changed yet?” Megatron asked, when Optimus came to the repair unit where he was getting most of his chest wall put back together.

“No!” Optimus said.

“And yet here you are,” Megatron said.

“I’m—checking on all the casualties!” Optimus said, which he absolutely was. “I can’t believe your main concern right now is about whether I want to ’face you.”

Megatron sighed. “Our military position is currently secure, I am not in fact very patient, and a million years has been long _enough._ ”

“What, you’ve been saving yourself the whole time,” Optimus said with a snort.

“What odd ideas you Autobots have,” Megatron said. “ _Saving_ myself, as though the capacity degrades with use. No, of course not; not long after my sparking, I exercised the mechanics sufficiently to satisfy curiosity and determine my requirements for a consort. Since then, I have not had the prospect of filling them.”

Optimus stared at him. “In _a million years?_ ”

Megatron shrugged. “I am more inclined to patience than I am to compromise.”

“And—after that, after all that time, now you want—” Optimus abruptly pulled up and blurted, “I’m going to go check on the infantry soldiers,” and just ran away.

But it kept gnawing at him horribly. The idea that Megatron of all people really thought it was worth waiting a million years for _him_ , worth giving up a massive strategic advantage to _have him_ —Optimus didn’t want that to make him feel differently about _himself,_ he didn’t want Megatron’s opinion to matter that much. He didn’t want it to matter at all. But—his whole life, everyone had mostly treated him like a second-rate model. Getting the spacebridge repair command had been a consolation prize for washing out of the Academy. Even after he’d managed to stop Megatron— _Megatron_ —with a rag-tag band of repair bots and, to be fair, a whole lot of luck, the Council had patted him on the head, left Sentinel in command until Ultra Magnus recovered, and then tossed him into a minor post. Like they’d thought it was _all_ luck. And the truth was, he’d more or less agreed with them.

Except now here was Megatron himself saying that was not just wrong but stupidly wrong. As if Optimus was— _special._ Megatron. The half-mythical Decepticon leader who had nearly conquered Cybertron outnumbered eight to one, who had fought all the greatest Autobot leaders of the last million years, and if anyone was qualified to say _the greatest military leader your people have ever produced,_ it was him.

Which had zero to do with wanting to _interface_ with him, which Optimus didn’t even a little bit want to do, because Megatron was a tyrant who wanted to conquer Cybertron, and you couldn’t make up for that by being good at it. Anyway Megatron was a _jerk,_ and violent and terrifying and insanely overpowered and _dangerous,_ even getting anywhere near him and his oversized servos was crazy; actually _interfacing_ with him would be breathtakingly stupid, Optimus had fought him enough to know if he ever let Megatron actually lay hands on him, he’d be completely at his mercy, struggling and helpless against all that vast irresistible strength—

Optimus had to violently preempt his entire conscious train of thought and shove it hard, trembling, and he couldn’t actually get it killed off, he could only let it drop into background processing. He had never actually worked out before what he really wanted from interfacing, and now he was trying really hard to _keep_ not working it out, only his traitorous subconscious processing system was going around him—no thanks to Megatron and his _sick_ and _twisted_ idea of flirtation, his enormous hand pressing down on Optimus’s throat with vivid, alluring detail—

Optimus sequestered that entire train of thought in a cordoned-off section of his processing before he went back to check on Megatron again the next morning. As he came into the room, a bot he didn’t recognize was pouring an additive into the energon feed going into Megatron’s central line. “What’s that for?” Optimus asked, and the bot twitched violently, looked around with guilt written on his face like a direct neural transmission, and Optimus didn’t even think; he was lunging across the space and slicing through the feed line just millimeters ahead of the faintly green surge traveling down its length.

The tussle afterwards was over pretty quick, and Optimus stood up panting from the trussed bot and found Megatron awake and smirking at him with enormous satisfaction. “So it _did_ change your value equation,” he said gloatingly.

“Somebody just tried to _kill_ you, and that’s what you’re thinking about?” Optimus said through his clenched jaws.

Megatron shrugged. “He was not going to succeed. I had begun rousing; my reflexes are sufficiently quick to have stopped him myself. If not so swiftly as _you_ did,” he added, _caressingly_. “You didn’t even have to run a conscious evaluation, did you? Come and help me detach from these cables.”

Optimus was halfway into a furious and spluttering denial when that cut it off. “What? You only just got patched up—”

“My condition will not further improve under the care of your medics,” Megatron said. “Your Council has also reached a new value equation, clearly,” he nodded towards the bot on the ground, “and that it is as wrongheaded as most of their other calculations will not prevent them from causing me irritation.”

Optimus stood blankly. Megatron was right, obviously. The bot lying there hadn’t done this on his own. The Council had just—tried to murder Megatron. While he was still recovering from saving all their lives. Exactly the way Megatron had expected them to. Optimus put a hand over his face, his intakes cycling violently, and jerked back up only when Megatron caught him by the chin and tipped his head up to study his face with those gleaming red optics, a little thoughtful.

“I assumed you were merely performing a display of loyalty,” Megatron said. “Did you truly not believe they would try to kill me? It is far more rational than most of their other decisions.”

Optimus stared up at him. “Why aren’t you even— _angry?_ ”

Megatron shrugged. “I am angry about many things your idiot leaders have done, but they have made no secret of being my enemies. If I didn’t expect them to kill me, I would only be a fool. I don’t intend to give them further opportunity. Now, are you going to help me get to the Nemesis, or are you going to summon your security?”

“I’m not going to call security on you! That’s not the same as—” Optimus said, but Megatron just raised a faintly impatient brow and Optimus clenched his teeth and said, “ _Fine,_ I’ll help you,” and used his clearance to open all the doors on the way to the hangar bay, Megatron limping behind him, the slight drag of his steps just enough to put Optimus on anxious edge. When they reached the bay, the officer on duty did try to call security. Optimus ground his jaw and reached out and grabbed the officer’s arm, ignoring Megatron as much as he could when he could _feel_ him radiating dry amusement right at his back.

“What exactly do you think happens if you call security to try and stop Megatron going back to his own ship?” he said.

“I—” the officer stammered, darting a look up at Megatron. “We’ll—”

“There’s going to be a _fight,_ ” Optimus said. “Let’s be optimistic and say we win the fight. You think the other Decepticons are going to stick around and help us when the Marenil come back after we take out their leader?”

The officer agreed to just quietly turn his back while Megatron flew away instead. That was when _Megatron_ turned recalcitrant. “Not alone,” he said firmly, at the edge of the bay.

“You think I’m coming with you?” Optimus said incredulously.

Megatron shrugged. “Abandonment is grounds for the severing of a consort bond. Therefore I will not do it. If you will not come, I will not go.”

“If you stay here a lot longer, the Council will find out!” Optimus said.  “And they _will_ send enough security to stop you.”

“To kill me,” Megatron corrected him. “Certainly they will try. Many have tried to kill me. None have yet succeeded. I do not make decisions primarily on the basis of avoiding danger. It is a tertiary factor at most. _You_ are far more important to me.”

Optimus stared at him in outrage so violent that he missed half his own mechanical responses and had to scramble to manually stop his interfacing subsystem from transmitting a signal of _willing interest_ to Megatron. He forcibly dumped his emotional processing to get rid of the uncontrollable thread, and in the very painful clarity left afterwards in his own head, he realized with sharp certainty that Megatron was _right_ about the value equation. Cybertron’s defense needed Megatron, Optimus could see that, and even worse, he could see that he— _wanted_ Megatron. He _wanted_ to be carried off to the Decepticon flagship and to Megatron's quarters where he’d be luxuriously and thoroughly conquered by his unbelievably gorgeous consort who had just saved his friends and his entire planet, in fact his rationality center was starting to have trouble working out the logic of refusing, why _was_ he just standing here instead of getting fantastically laid and—saving Megatron’s life, which had somewhere along the way gotten assigned a much higher priority level. The twisted pile of scrap had _gotten_ to him, and if they stayed here, and the Council did send in a squadron to kill Megatron, Optimus was going to end up _fighting them_ for _Megatron’s sake._

He glared savagely at Megatron, who had totally done all of this to him _on purpose_. “You know, you wouldn’t have to _worry_ about technicalities if you’d tried _asking nicely_ in the first place.”

“Such an Autobot thing to say,” Megatron said tolerantly. “As though I didn’t value you enough to claim you by any means necessary? Besides, you could hardly have accepted me voluntarily. You would have been a traitor. Shall we go?”

There was clearly something deeply wrong with Optimus’s processing centers, because that was starting to make sense. “This is all your fault,” Optimus said bitterly, and grabbed his jet pack off the wall.

It was almost unbearable after that: the flight across the vast gap in space, landing on the Nemesis, the roar of noise among the Decepticons as they welcomed Megatron back, throngs of mechs fawning over him, nearly _worshipping_ him, and Optimus just wanted it _over_ already; he wanted, he _wanted,_ and then at last Megatron finally turned back to him, and took him alone down a corridor to a huge but spartan chamber with a massive recharge bed, more than big enough for him to spread-eagle Optimus out in the middle like a feast ready to be devoured, and said, “The Marenil will make a first probing attack in the morning, I suspect.”

“Yeah, sure,” Optimus said, distractedly, not really listening; he couldn’t jerk his eyes away from the bed, and then Megatron caught him by the shoulder, turned him around as easily as if he was made of tin, tipped his head back and _kissed_ him, a deep rough aggressive kiss, his hand cupping the back of Optimus’s helm and holding him in place while Megatron mapped out every contact point inside his mouth, brief teasing flirtatious bursts of data, offering key exchanges that Optimus completed instinctively, without even a pretense of hesitation. He was gripping Megatron’s waist by the end of it, bracing himself, _ready,_ and then Megatron disengaged and sighed with immense deep satisfaction and said, “You should rest. Sleep well, my consort,” in a purring, caressing tone, and— _left._

“I hate him _so much_ ,” Optimus said blankly, standing in the middle of the room alone.

#

The Marenil _did_ attack the next morning. Optimus hadn’t rested all that much; his brain kept cycling through awful lurid fantasies where Megatron came in while Optimus was in recharge and bound him to the corners of the platform and then roused him so he’d consciously experience being mounted, Megatron’s spike irresistibly extending into him, claiming every connection point along the way, until he reached Optimus’s spark chamber _,_ and blasted all his channels with pleasure until Optimus finally gave up even that, let Megatron have all of him, completely—

The alarm klaxons blew through that particular stray processing loop, and Optimus jumped to high alert and rolled off the bed and was halfway down the corridor before he belatedly realized he didn’t know where he was going, since he’d been too overheated last night to get the ship mapped into long-term storage. Decepticons were pounding in both ways around him, and Optimus gritted his teeth and accessed the consort interface to find out where Megatron was. He aggressively ignored the emotional response his system produced when Megatron instantly responded to the query with a surge of vivid and unquestionably sincere pleasure alongside the directions.

Optimus came out into the ship’s launch hangar and found the Decepticon ranks lining up; Megatron himself was getting ready to lead them off. “I will be leading in the field,” Megatron told him, turning as Optimus dashed up to him, weaving through the massive warmechs all over. “Take command of operations here and organize the counterstrike. You see the six alternatives?”

“ _Seven,_ ” Optimus said, pointedly.

Megatron looked at him and said, “If you think it wise,” and Optimus couldn’t help but understand what he meant: if they did run the counterstrike maneuver that relied on having the Autobot forces hold the sixth quadrant, then as soon as the Marenil were pushed back, the entire Decepticon force would be exposed to them, wide open for a flanking maneuver. And Ultra Magnus would be in command over there, under the authority of the Council—

He looked away, feeling miserable, and then Megatron caught his chin in a curl of his finger and tipped his face up. “I leave it in your hands,” he said, and Optimus couldn’t help himself, he stretched up on his toes and pulled Megatron down to him and kissed him, Megatron’s arm coming around him and lifting him off the ground to kiss him harder. Then he put Optimus down and turned and marched straight off the hangar’s edge into space, transforming as he did, and the other Decepticons poured out after him.

Optimus stood looking after him dazedly for a moment before he managed to shake himself out of it, and he ran to the command center. It didn’t occur to him until he burst in and half a dozen Decepticon officers turned to look at him that Megatron had just handed him his operations, and what if those officers didn’t exactly feel like obeying an Autobot? It didn’t help that the _smallest_ one was roughly twice his size. “Right,” Optimus said, determinedly showing no doubt, and marched himself to the center of the room, although he didn’t try sitting down in the command chair: it would’ve made him look like Sari perched on Bulkhead’s shoulder dangling her legs. “Let’s get the full battlefield on this screen, and I want casualty reports going here.”

Having to fake confidence for the Decepticons was a good thing, actually, because it distracted him at least a little from the fact that he wasn’t actually a hundred percent sure what he was _doing_. The biggest force he’d ever overseen was the forty-mech squadron back at the mining colony six weeks ago, defending a simple surface-based border. And they’d all been Autobots who’d come through the Academy: he knew what they could do backwards and forwards. Now he had five thousand Decepticon warriors on his hands, any ten of whom probably were the equivalent of his entire squadron in military capacity, spread out across a vast and fully three-dimensional front.

He was terrified thirty seconds into it that he was going to lose track of something: he’d never tried to keep a battlefield this big in his head all at once even in military exercises in the Academy. But he _couldn’t_ lose track of any of it, because if he did, mechs— _Megatron,_ his brain inserted, jolting the anxiety higher—might _die;_ he had to hold on to it all and keep the map in his head, where everyone had to be, how they’d pivot into their counterstrike positions so they could hit back without letting the Marenil regroup and escape through the spacebridge again, and without letting _them_ make a counter of their own.

It was brutally hard: almost like fighting Megatron, only Optimus was fighting a thousand Megatrons at once with a thousand arms to do it with, any of which might go flailing off unpredictably at any time. He had to desperately grab resources away from every other part of himself: his locomotive system, the sensory system; he even pillaged his emotional subsystem, the whole world going clear and sharp-edged, focused on the terrible dance of battle and the scrolling lines of details running past him on the casualty lists, each one a small but crucial shift in the situation that had to be accounted for.

Somehow he managed it, hearing his own voice calm and steady issuing orders: _send the third red squadron to reinforce that weak point in sector seven,_ circling a region on the battlefield map with a stylus _; order battalion three to hold position; tell Megatron the back perimeter looks wobbly,_ which he knew Megatron would understand: one after another rolling out of him, and the Decepticons in the command center started to obey them quicker as they went on. Their hunched shoulders and bristling armor somehow even seemed to go less spiky, as if they’d all secretly been braced. And why _shouldn’t_ they have been: the only reason they’d had to trust him was—the same reason that _Optimus_ had, to trust himself in a way he’d only ever done before out of necessity. Because _Megatron_ had said so.

And Optimus hadn’t wanted it to matter, but it did, of course it did; it mattered more than anything to have someone tell him _you can, you’re worthy, you’re strong enough,_ to give him the gift of trust; and yes, Megatron was utterly ruthless and careless of others, but at the same time—Optimus had put him in a _prison,_ and Megatron hadn’t let that stand in the way of reaching out for him, for his _enemy,_ even leaving himself wide-open to do it: _I don’t make decisions on the basis of avoiding danger,_ so at least he was ruthless with himself, too.

It felt like—a puzzle he was on the edge of solving, an answer just out of sight. Optimus had to shove it hard to keep it from teasing away more of his brain—he _needed_ his brain right now—but it stayed lurking down in deep background processing, sending up faint glimmers through the steady marching tactical analysis. The Marenil were falling back all across the front, their forces staying in deceptively good order: Optimus could see the weaknesses, though, the holes that in a few moments he’d tell Megatron to punch through. He was almost done evaluating the situation, getting ready to choose the best counterstrike position, and then the officer on comms said, “Lord Optimus—” Optimus was saving a more extensive yell about the _Lord_ for after the battle, since telling them thirty times so far hadn’t gotten them to drop it, “—the Autobot Magnus hails you!”

“Put him on,” Optimus said, and Ultra Magnus appeared on the screen. “Optimus!” he said. “They’re on the run. There’s an opening for a counterstrike,” as urgently as if he’d just seen the possibility _now_. “We’ll take the sixth quadrant. Tell the Decepticons to come at them from the fifth and seventh, and we’ll get them in a pincer sweep!”

All the Decepticons in the command center paused over their consoles, glancing back at Optimus. He stood looking at Ultra Magnus, who frowned and said, “Did you receive? Is there something wrong with the connection? Get moving!”

“I’m not here giving the Decepticons orders under your command, Ultra Magnus,” Optimus said. “I’m acting on behalf of _my consort_. You remember him, tall, silver, big gun, saved your aft the other day?” Ultra Magnus stiffened. “I had to sneak him off our medical support ship yesterday because a Council agent tried to murder him. So before I hand you the entire Decepticon rear on a platter, I need to know that you’re not planning to hit them the second they finish saving you from the Marenil. _Do_ I know that?”

 Ultra Magnus said indignantly, “Of course we’re not going to hit them! Prime, I think you’re forgetting who you’re talking to—”

“I’m talking to the mech who nearly lost Cybertron six days ago,” Optimus said flatly, and Ultra Magnus actually flinched back, his face shocked; Optimus actually could see other Autobots in his command center jerk up from their stations and trade horrified glances. “You’re talking to the one who’s trying to save it. That opening you just spotted is there because I’ve been _aiming_ at it for the last four hours, and because Megatron’s bought it for us with almost three hundred Decepticon casualties. I don’t want to think how many of their sparks have gone out by now. And in that time, there’ve been less than twenty Autobot casualties, because while we’ve been fighting to win this thing, you’ve been running a zero-flat defensive maneuver to minimize your losses.”

Magnus made a small abortive move of protest; his optics darted side to side like he was worried that the Decepticons around Optimus would overhear _._ Optimus shook his head. “Did you think the Decepticons wouldn’t _notice?_ There’s two screens right here monitoring Autobot movements; every senior staff officer has been watching you dance around while their people are dying, and I’d bet that at least half of them are quietly running backup ops out of my sight because they’re waiting for you to turn on them—and they’re expecting me to _help_ you.”

Turned out it was more like nine-tenths: Optimus could tell by the wave of nervous twitches that went around the Decepticons. “I don’t blame them,” he told Magnus, without looking away. “But they’re wrong about me. I’m _not_ going to help you. The only thing I’m willing to do—is give you a chance to prove them wrong.”

Ultra Magnus stopped with his mouth half-open, off-balance. “What?”

“We _should_ do the pincer maneuver,” Optimus said flatly. “It’s the best of our options. It’ll demolish the Marenil fleet completely. They’ll have to pull the remnants back all the way to their own space to protect against a counter-invasion. It’ll protect Cybertron from all of them. But I’ll only do it if you promise that afterwards—when you have a clear shot at the Decepticon rear, and the Council orders you to take it—you’re going to say no, and stand down instead. You and your entire senior staff. I need all of you to give me your word. And if you break it—” He swallowed. “If you break it, then at least I’m already where I need to be.”

Uncertainty was wavering on Ultra Magnus’s face, and he blurted, “If we stand down—the Decepticons will have a clear shot at _Cybertron_.”

“And if they don’t take that shot, we could get the shields back up and keep them off their own homeworld for another million years,” Optimus said. “And if we don’t put the shields back up, they could conquer the planet and take it away from us. And if they don’t do _that_ —then I guess we could all negotiate a treaty and figure out a way to live together in peace again. I think that sounds pretty good, personally. How about you?”

#

“Hrmm,” Megatron said, a dissatisfied rumble, scowling at the monitors showing the Autobot ships, all of which had unquestionably stood down. Ultra Magnus had ordered their weapons powered completely off, and he’d sent what looked like half his crews to comb the battlefield for casualties, with medics along; Optimus could see them actually doing triage right in the field, and others towing the disabled warriors back to the medical frigates, which Ultra Magnus had put out front between their forces, with the shields completely down. “And I suppose now you want _me_ to stand down. Even though it will take less than sixty hours for the Council to restore the planetary shields.”

“Yep,” Optimus said, serenely. “But they aren’t going to, anyway.”

“Why _not?_ ” Megatron said.

“Because Ultra Magnus and the entire army are out here with us,” Optimus said. “If the Council locks _them_ off Cybertron, Magnus is going to have to come to some agreement with us on his own. Which means that we’ll end up with a peace treaty between you and Magnus that none of them get to help negotiate. I’m pretty sure they’d hate that even more than having to make a deal with you themselves.”

Megatron grunted faintly. “I wonder if they’ll have thought that far ahead.”

“I sent them a note,” Optimus said. “I figured it wasn’t worth taking the risk.”

Megatron looked around the command center: most of the staff were gazing with longing expressions at operational outlines on their displays, clearly designed a long time ago, for a rapid-fire planetary takeover. From what Optimus could see, it would take them roughly sixteen hours to take total control of Cybertron. Megatron looked back at him, and Optimus smiled up, completely unworried.

Megatron’s optics narrowed. “Stand down the fleet.” 

Everyone in the center slumped, heaved sighs of disappointment going around. Several of them cast last tearful looks at their displays before they cleared the consoles. Literally; Optimus heard more than one small hiccuping sob, and several of them gave each other comforting pats on the back. But there wasn’t the slightest hesitation, and Optimus felt more than a little bit like crying himself as he saw the weapons systems going down, and Decepticon medical and salvage crews started launching, joining the Autobots already at work.

He was still watching it happen through the faint rainbow glow of a thin lubricating glaze when Megatron added, “General Strika, you have the fleet.”

“Yes, my lord,” she said, saluting, and looked Optimus up and down for an evaluating moment before she moved past him to take the chair. Optimus blinked at her, and then his logic unit woke up and informed him that there wasn’t anything to do but cleanup until the Council had the chance to put up the shields and _didn’t_ , which meant Megatron had the next sixty hours free.

Megatron’s hand closed around the back of his neck, and Optimus tried desperately not to embarrass himself in the middle of the command center and completely failed; he turned around and flung himself into Megatron’s arms, kissing him wildly even as he was carried down the hall, back to that chamber and the huge recharge slab, and Megatron lowered him to it with his optics blazing and pinned Optimus’s wrists down to the surface with a hand and said, purring and insistent, “Open for me, beloved.”

Optimus dragged in air, already running so damn hot that it was an effort not to do it right away. He was _dizzy_ with lust. “ _Make_ me,” he gasped out.

Megatron groaned and grabbed him by the thighs. Optimus tried to get away the second his wrists were loose, firing one of his grapples at the wall to pull himself free, but Megatron caught the cord mid-flight and wrapped it around his wrists instead, binding them tight to his chest, and shoved him back down flat and got his legs again, forcing them apart: Optimus tried as hard as he could to keep them together, but he _couldn’t_ , oh Primus, Megatron’s unbelievable strength, his massive hands so hot on Optimus’s thighs, spreading him open, vulnerable, helpless, and then Megatron put his _mouth_ on the access panel and hummed low and deep against it, and Optimus squeaked involuntarily. “ _Megatron_ ,” he groaned, his hips pushing up into it; he couldn’t _help_ it.

Megatron laughed softly against him, triumphant. “Yes, my love. The moment of your conquest is at hand. Yield to me.” He dropped a kiss on the panel.

“Nnnh,” Optimus said, a whimper. “N-not— _yet_.” He tried to squirm loose, and he couldn’t, Megatron was holding him so tight, and then Megatron _licked_ over the panel lock, and it popped open before Optimus could stop it.

Megatron moved so fast Optimus instinctively went into combat mode, everything revving up, and he barely even registered the actions in sequence: Megatron’s thumb shoving the panel open even as he stood up, hauling Optimus down to the end of the bed, spike already out and _waiting_ , and he pulled Optimus _onto_ it without a pause, shoving it in so hard that Optimus actually cried out, pain shocking through him in a dazzling, spark-brilliant wave, all his systems lighting up; he squeezed his optics shut and bit his lip to stifle himself, shivering wildly through the jarring moment, and when he let his head fall back gasping and opened his eyes, Megatron was gazing down at him incandescently bright, optics glowing with intensity and watching him hungrily, and Optimus quivered all over again, flinching with the tiny sparks of pain as his valve tried instinctively to expand and contract around the massive spike head already straining him to his limits, ready to press in further.

“Yes?” Megatron breathed out to him, tenderly, asking.

“Yes,” Optimus said, crackling. “Oh, yes. _Yes,_ ” and his voice was going high and thin and a little shrill as Megatron pressed steadily and ruthlessly into him, strain reports going off all over his body—all of them hovering precisely and perfectly short of damage, with exactly enough of a margin that Optimus could just barely keep struggling, keep trying to twitch and squirm in tiny movements that sent sparks of intense, stinging shocks running down his circuitry.

“How exquisitely you suffer,” Megatron said, sounding almost in pain himself, bending to kiss Optimus fiercely, over and over. “Tell me, do you feel it in your very frame now, how struggle is useless? How completely you are in my power?”

Optimus sobbed out a laugh, breathless and half-strangled and joyful, because this was the best he’d ever felt in his _life_ , his whole brain lit-up and dazzled with pleasure and pain and sensation and something even more glorious, the last puzzle pieces falling into place: Megatron _had_ him and Megatron could do anything he _wanted_ , and what he _wanted_ was to make Optimus feel this way.

And in the morning, or more likely sixty hours from now, Optimus would tell Megatron _no_ , not for himself but for the other Autobots, who for some insane reason _didn’t want this_ , the wild, intoxicating rush of pain and pleasure and excitement and fear all surging through their processing at the same time: they were only terrified of it, and doing stupid and cruel things in their fear, and when Optimus told Megatron _no_ for them, when he told the Decepticons _no_ , the Decepticons would _stop._ And try to find other ways of getting what they wanted, like for instance showing off how great it was to have them on your side.

But he wasn’t going to say no any time soon. “More,” Optimus said, rasping it out with an effort. “Make me—make me feel it. Make me— _yours_ ,” and Megatron groaned, a deep shuddering all through him, and he caught Optimus up in his arms and pulled him into his arms, pushing him _down_ onto his spike, and sending out a crackling burst of power that made Optimus’s entire vision center go offline for a moment, his whole body trembling violently. He swam back up through a haze of sparkles, limp in Megatron’s arms, his head lolling and dazed.

“Yes, my own,” Megatron was murmuring, kissing him again, taking his gasping breaths. “You are _mine_. I will never surrender you, my darling, my shining spark.”

“Oh,” Optimus choked out another sob. Megatron was extending into him, heading for the spark chamber inexorably, and Optimus was going to make him _work_ for it. “Oh, Primus, Megatron, I love you so much.”

# End

**Author's Note:**

> With many thanks to monicawoe for beta! All fb loved! <3 Here or [DW](https://astolat.dreamwidth.org/311236.html), [tumblr](https://astolat.tumblr.com/post/182614572663/a-degree-of-compatibility-8500-words-by-astolat), or [fediverse](https://fandom.stopthatimp.net/channel/astolat/?f=&mid=73b7cbeaf585e1145ddfba2b3029f21e37844e80567a11ca3656f3816fe63f76@fandom.stopthatimp.net)!


End file.
